U.S. Code of Federal Regulations
Regulations most recently checked for updates: Aug 27, 2025
Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for existing sources (PSES):
Subpart BO—Zinc Chloride
| Pollutant or pollutant property | PSES effluent limitations | |
|---|---|---|
| Maximum for any 1 day | Average of daily values for 30 consecutive days | |
| Milligrams per liter (mg/l) | ||
| Arsenic (T) | 3.0 | 1.0 |
| Zinc (T) | 2.3 | 0.76 |
| Lead (T) | 0.18 | 0.048 |
